Maximum Admissible Slip of Tractor Wheels without Disturbing the Soil Structure

Round 1
Reviewer 1 Report
The title of the article is incorrect! Due to the driving torque applied to the wheels, there is always a slip in the tyre-soil connection! And this slip destroys the soil in all cases. Figure 4 completely contradicts the experience so far. If the rolling resistance increases, the slip must also increase! According to the figure, this is exactly the other way around! As long as these major mistakes aren’t corrected in the article, there’s no point in dealing with it! In Figure 5, the slip is probably not given in%, but in decimal!
Author Response
Thanks for your suggestions and reprimands.
The answers and explanations are in the attached file
Best regards
prof. A. Aboltins
Author Response File: Author Response.docx
Reviewer 2 Report
The manuscript face a very important topic in agricultural engineering that still needs to be investigated and updated. Tractor slip is a very complicated topic since involve mechanical parts but only soil that is a very complex and variable substrate subjected to change in time and space. The Authors showed the capability of permorming an experimental test and acquire valuable data but in my opinion the manuscript is not acceptable in the present form. It needs to be completely rewrited and better organized.
Introduction:
The equation 1 should be reported in this section if it is part of the state of the art and to explain what is missing and needs to be investigated, not in the case is part of the material and methods.
Ref 21 seems to be related to the determination method of bulk density
At the end of the section state clearly and briefly what is the scope of the manuscript.
Materials and methods section
Without knowing precisely the scope is not easy to follow the materials and methods used. In any case some information are missing considering:
numer of replicates to calculate ks and bulk density;
operating depths of the plough unit
Results section
The first statement is very strong and incomplete. ASABE D497 reports in detail all the parameters involved in slip of tractor wheel. Of course rolling radius is one of that but the concept is much more complicated. What about the mass, load, inflation pressure? In any case this is not a constructive parameter of the tractor because tractors of same power could mount different tyres, is very common among different brands.
Title of the manuscript is very attractive but in my opinion to state that you must study the tractor on a very broad range of conditions.
In all the results section is not present a table reporting data and its analysis.
Try to reorganize the data and the manuscript.
Author Response
Thanks for your suggestions and reprimands.
The answers and explanations are in the attached file
Best regards
prof. A. Aboltins
Author Response File: Author Response.docx
Reviewer 3 Report
The paper is well organised and above all in introduction the topic is very well explained.
There were a few areas which I would like to point out to the authors for their consideration in improving the manuscript:
Theoretical consideration provides a good insight into this phenomenon, but the discussion and conclusions of the research should reveal the novelty of the study in more detail. Adverse changes in soil physical properties due to tractor wheel slip in excess of 15% have been described by many researchers in previous sources. In the article discussion, the authors need to justify what is new and unique about this research effort?
It is known that when assessing the performance of a tractor in terms of traction efficiency and soil compaction, it is also important to assess the slip of the tractor drive wheels. Increased or high flexion tires and reduction of inflation pressure is currently widely used to reduce the slippage of tractor drive wheels. Please provide more details in the theoretical calculations of how you estimated the tire type and its inflation pressure. Provide information on tire inflation pressure during the experimental test?
Moreover the discussion on rolling resistance appears not correlated with the results. In detail it has to be improved in material and methods why has been developed the study on rolling resistance and improve how the related results are correlated with the wheelslip and working quality.
Also discuss in more detail how your work is put into practice. It is important to discuss how your research can be generalized and used (other tractors, other field conditions, tire of other type, tires of other parameters).
Author Response
Thanks for your suggestions and reprimands.
The answers and explanations are in the attached file.
Kind regards
prof. A. Aboltins
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Dear Authors, Dear Publisher,
I have read the response to my review and still continue to uphold it.
The slip is generated in 3 places in the wheel-soil connection. It is significant along the wheel-soil connecting surface, medium in the soil (among the particles of soil), and small in the tire. The article depicts a plowing tractor (Fig. 3) when the traction force is significant, there are sure to be displacements in the soil structure under the drive wheel. I do not support the publication of the article in its current (revised) form either.
Author Response
Thanks for the review.
Explanations for misunderstanding are attached to the additional file.
Prof. A. Aboltins
Author Response File: Author Response.docx
Reviewer 3 Report
I agree with the revised version of the article. I think this version of the article can be printed in a journal.
Author Response
Thanks for the positive review.
Prof. A. Aboltins